原句I have been away from Shanghai for 3 days为什么不能改成 I have be

原句I have been away from Shanghai for 3 days为什么不能改成 I have be I 've been away from shanghai for3 days"是被动语态吗?为什么能用have(has I have ever been to Shanghai改成否定句 I have been working for two days. I have been away for business for many days,and my sunflower Have you ever been to Shanghai?Yes,I （）there for three days I have been away from my home for tow months,so I ___ my par I have been to Shanghai I have been in ShangHai from 12 July. Have you been to Shanghai?Yes,I ( )therefor 3 days last mont i have been to shanghai为什么加been? I have been in Beijing for two days.(同义句) I _____ to Beijing